Marine biologists have an explanation for the mass gathering. They say it's the time of the year when sharks migrate and head for warmer waters.
This week they were spotted in two different groups near the Boca Raton Inlet.

The mass congregation also has a positive side at a time when shark numbers are in serious decline.
According to Boca Raton ocean rescue, this happens annually around this time of year. Here's the video of the 2011 shark migration in the Florida beaches.